The Dancing on Ice judge – who did not share the cause of death – took to Instagram on Saturday to share a carousel of photos of herself and her relative, who she called her "best friend" and "sister" alongside a touching tribute.
WATCH: Oti Mabuse struggles to hold back tears on Dancing On Ice
"How is this the last time I would hold you in my arms. I am so shattered inside I can't even begin to describe the pain. This is not how this was supposed to go," Oti began.
"We had plans together, travel the world and dance on a beach in Jamaica for my birthday [broken heart emoji]. I used to fetch you everyday from crèche, swimming, chess since we were 8. You were only 28 yet the kindest, sweetest human being in my life!"
Oti continued: "I've lost my niece, my little sister, my best friend. Life dealt you the harshest card but you always chose to win, you always fought to come out the other side above it all with a smile on your face.
Oti shared several sweet photos of the duo together
"I love you much with all my heart and now you're gone and I feel lost in more ways than one to a pain I've never felt before. I'm still calling you and texting you trying to understand - how? Why?"
She concluded: "May you rest in peace and power my sweet Tlhogi. Say hi to Koko, Abuti Neo Le Malume Tshepo. I promise to take care of Sesi, Nanikie and Mpho for you x."
Oti's fans and former colleagues were quick to offer messages of support and share their condolences, with Dianne Buswell responding: "I'm sorry for your loss oti xxxxx sending lots of love."
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